Classifying apparatus and method



Oct. 7, 1952 N. J, WOODLAND ET AL 2,612,994

CLASSIFYING APPARATUS AND METHOD Filed Oct. 20, 1949 s Sheets-Sheet 1FIG.6 I FIC3.7 FIG-.8 FIGQ mvEN-roRs:

NORMAN J.WOODLAND BERNARD SILVER BY THEIR ATTORNEYS NOTE= LINES 6,7,8,AND 9 ARE LESS h wwn/A REFLECTIVE THAN LINES I0. I W

1952 N. J. WOODLAND ET AL 2,612,994

CLASSIFYING APPARATUS AND METHOD Filed Oct. 20, 1949 3 Sheets-Sheet 2Oct. 7, 1952 N. J. WOODLAND ET AL 2,612,994

CLASSIFYING APPARATUS AND METHOD Filed Oct. 20, 1949 3 Sheets-Sheet 5POWER JUPPLY v [is $31131,

Patented Oct. 7, 1352 2,612,994 CLASSIFYING APPARATUS AND METHOD NormanJ. Woodland, Ventnor, N. J., and Bernard Silver, Philadelphia, Pa.

Application October 20, 1949, Serial No. 122,416

11 Claims.

This invention relates to the art of article classification and hasparticular relation to classification through the medium of identifyingpatterns.

It is an object of the invention to provide automatic apparatus forclassifying things according to photo-response to lines and/or colorswhich constitute classification instructions and which have beenattached to, imprinted upon or caused to represent the things beingclassified.

Another object of the invention is to provide a novel method by whichclassification patterns consisting of different identifying combinationswithin a fixed pattern area are utilized to identify different articles.

A further object of the invention is to provide photo-sensitiveapparatus which shall classify things without recourse tocharacteristics of the things themselves for classificationinstructions.

Another object of the invention is to provide photo-sensitive apparatuswhich shall classify things or their tokens which are caused to movewith motion of translation past the photo-sensitive apparatus withoutorientation of those things with respect to the direction of translatorymotion.

Another object of the invention is to provide photo-sensitive apparatuswhich can serve as sensory and classifying organ for tabulating,computing and sorting machines.

More concisely stated, it is an object of the inventionto provide anautomatic apparatus that will execute with precision and dispatchclassifying orders which are given to it and will yield up the resultsof the classification process in an intelligible manner.

One application of the invention is in the socalled super-market field.An embodiment of the invention in this application will be described indetail, but it should not be considered that the invention is limited tothat field only. The novel featuresthat we consider characteristic ofthe invention are set forth with particularity in the appended claims.The invention itself, however, both as to its organization and itsmethod of operation, together with additional objects and advantagesthereof, will best be understood from the following description ofspecific embodiments when read in connection with the accompanyingdrawings, in which Fig. 1 is a pattern used in coding classificationinformation;

Figs. 2 through 9 are patterns evolved from Fi 1;

Fig. 10 is a modification of the pattern of Fig. l;

' practice of the invention in accordance with Fig. 11;

Fig. 13 is a right side view of another element utilized in accordancewith Fig. 11;

Fig. 14 is a block drawing of the electronic circuit utilized in theembodiment of the invention diagrammed in Fig. 11;

Fig. 15 is a schematic drawing of the electronic circuit utilized inaccordance with Fig. 11; and

Fig. 16 is a graph utilized in the explanation of the operation of theelectronic circuit of Fig. 15.

Fig. 1 shows, a pattern of white lines I, 2, 3 and 4 on a darkback-ground 5. Line I is a datum line and the positions of lines 2, 3and 4 are fixed with respect to line I. There are, then, fixed placesfor three lines 2, 3 and 4 in the pattern, and these lines are termedinformation lines. While the lines have fixed places in the pattern, thelines do not necessarily fill the places. For example, line 4 is missingfrom its place in the pattern in Fig. 3. A zero (0) is associated with avacant line position and the numeral one (1) with an occupied lineposition. The information pattern of Fig. 3 could therefore be replacedby the code number and the pattern of Fig. 4'by 101. The informationlines have particular weigh-ts assigned to them; line 4 is 2, line 3 is2 line 2 is 2 A digit (1 or 0) associated with a particular lineposition in the code number is used as the coefficient of the weightassigned to that line position. The information in Fig. 3 is thereforedecoded as follows:

showing that the pattern in Fig. 3 represents classification 6, or thesixth classification, which in practice could be 6, department F orvolume vi, etc. Similarly, Fig. 4 yields up classification 5. It is seenfrom Figs. 2 through 8 that three lines in different combinations can becaused to represent seven different classifications. If one more linelocation were included in the pattern, eight more classifications wouldbe made available; another place would increase the total by sixteen;another by thirty-two, etc. By the incorporation of more and more placesfor lines into the pattern, the number of classifications grows veryfast and can be made large without limit. For example, if there areplaces for ten classification lines in the pattern, the number11111,11111 is available. This is decoded as follows:

ner as a particular line position. Further, if theparticular colorsradiated by the lines are produced by the impinging of ultraviolet lightupon fluorescent pigments, the corruption of the pattern by anyextraneous non-fluorescent colors in the neighborhood of the pattern isaverted. The present embodiment of our invention utilizes a pattern oflight and dark lines, but in certain of the modifications of ourinvention, a pattern utilizing several colors may be used withadvantage.

The straight line pattern of Fig. 1 is useful only where the pattern canbe oriented with respect to the photosensitive apparatus. The straightline pattern is modified into the circular pattern of Fig. 10 in orderthat orientation of the pattern be made unnecessary. Lines 6, 1, 8 and 9of Fig, 10 correspond respectively to lines I, 2, 3 and 4 of Fig. 1. Theseries of concentric circles II! has a function which will be discussedlater in thisdisclosure. As with the straight line pattern, byincreasing the number of places for lines in the pattern (or target) ofFig. 10, the number of classifications may be made large without limit.

In Fig. 11, a system is shown which is utilized for the purpose ofclassifying such articles as cans and other packages II in accordancewith the information incorporated into the pattern which is placed oneach package II in the form of a sticker or stamped mark [2. It may benecessary, for example, to classify the package-into seven pricecategories, namely 1c, 2c, 3, 4c, 5, Sc and 7c. It has been shown abovehow this may be accomplished'with three line positions, 2, 3 and 4.Accordingly, each package H is disposed, with the target I2 down, on atransparent conveyor l3 and advanced thereby to a region where it isstrongly illuminated by a plurality of suitable illuminating sources [4.

The radiations reflected by the bottom of the package H are projectedinto the optical and scanning element l5. If the element I5 recognizes apattern in a particular package, the displacement device !6 quicklypushes the package I l across the conveyor [3 and onto the deliverychute I! by means of which it is passed through the barricade 18 to bewrapped for removal from the premises. If the element l5 fails torecognize a pattern 12 on the package II by the time the package H hasleft the operating range of the element [5, the package I l continuesalong the conveyor l3 until it is automatically placed on the returnconveyor 19 which causes it to fail to pass the barricade l8 and returnsit toward the point of placement on the conveyor l3.

As described hereinafter, the scanning element includes sensing meanswhich is moved back and forth transversely of the conveyor l3. Thisinsures scanning of the pattern on each of the V4 packages ll regardlessof position of the package on the conveyor, thus eliminating the needfor accurate placement of the package on the conveyor.

The function of element I5 is revealed by Fig. 12. Light from the bottomof the package II is focused by the lens or plurality of lenses 20 ontothe ground glass screen 2|. The lens 20 and the distance from lens 20 toscreen 2 l' are so selected that a sharp image of the bottom of thepackage II is produced on the ground glass screen 2| regardless ofslight variations in the distance from lens 20 to package ll, animportant object 21 rides in the thread 25-26 and causes the carriage 21to oscillate through 'the'extent ofthe thread 25-46. If the pitch of thethread 25-46 is constant, except .on that portion where the thread 25-46is turning back on itself, the carriage 21 will oscillate at constantvelocity except during the small reversal time as the thread 25-46reverses. A light-tight box 30 with cover 3| is mounted on the carriage2! so that it has the reciprocating motion of the carriage 21. The cover3| is provided with an aperture 32 which admits light from a smallportion of the picture on the screen 2| to the photo-cell 33. Thephotocell 33 has two terminals, 34 and 35. The velocity of the carriage21- is sufiiciently great that there is positive assurance that thephoto-cell, or plurality of photo-cells, 33 will scan the centralportion [8 of every pattern l2 passing the scanning plane A-A. Of coursethe velocity of carriage 21 will depend to some. extent upon the speedof the conveyor l3, but. there is no. close relation therebetween.

The scanning element l5 and its associated electronic circuit have adouble function: they must see and recognize the target [2, and afterrecognition they must see and decode the classification instructions inthe target l2. The recognizable portion of the pattern is the centralportion H), which consists of a series of alternate concentric black andwhite circles. The white lines are highly reflective while the blacklines reflect very little light. Since the recognizable lines in arecentrally located within the pattern i2, all recognized targets 12 willbe centrally scanned, an important feature if the information in thepattern is to be correctly decoded. As disclosed previously, the lines6, l, 8 and 9 in the target 12 comprise the coded information. It is tobe noted that these lines are not as highly reflective as the whitelines in the central portion In. The means by which the invention auto.-matically recognizes the target l2 and translates the coded informationwhich is in the form of lines in the target l2 into intelligibleclassification information is schematically revealed in the blockdiagram of Fig. 14 and is revealed in detail in Fig. 15. It is to benoted, however, that this is only one of several systems which may beutilized in obtaining information from the target l2 and frommodifications thereof. As the aperture 32 passes over the picture on thescreenll, thereare. fluctuations in he-amount of light which strikes thephoto-emissive type tube 33. These fluctuations are due to the differentreflective qualities in the various portions of the bottom surf-aces ofthe packages H, and the light impulses are converted into electricalimpulses by the cell 33. As the photo-cell 33 passes the various linesin the target I2, impulses will be generated in the associated circuitand applied to the wide range amplifier 36 which is coupled to analerter 31 and also to a limiter 38. limiter, in turn, is coupled to astarting stage 39 and to as many information stages 40, 4| and 42 asthere are information line places provided for in the target l2. Thealerter 31 is also coupled to the starting stage 39. The informa tionstages 4!], 4| and 42 are used to operate a suitable device forindicating the presence or absence of the information lines 1, Band 9.

Specifically, a standard full-wave rectifier circuit 43 is employed toprovide proper filament voltages and the necessary direct currentvoltages, both positive and negative with respect to the ground of thecircuit, for the operation of the stages involving the photo-tube 33;twostage pentode amplifiers 44 and 45 which, together with theassociated circuit, acts to amplify the positive impulses generated bythe photo-tube 33; four thyratrons 46, 41, 48 and 49 which comprise, inconjunction with the associated circuit, a standard scale of eightimpulse counter which acts to count all pulses of a predeterminedamplitude or higher and which, if eight impulses are counted within apreset time interval, acts to alert the starting tube 50; a limiter tube5|, also coupled to the output of the wideband amplifier 36, which,together with its associated circuit acts to limit all pulses passingthrough it to a predetermined amplitude; a shield-grid thyratron 50which starts the information stages 45], 4! and 42 when the correctvoltage is applied to the shield grid of the thyratron 50 by the alerter3'1! and to the control grid of the thyratron 55 by the limiter 5| andthree information stages utilizing shield grid thyratrons 52, 53 and 54to whose shield grids a starting voltage is applied successively bythyratrons 55, 55 and 5! respectively and then cut oif after successiveshort periods by thyratrons 58, 59 and 60, respectively.

The photocell 33 is connected through terminal 34 to a. positive tap onthe power supply 43 with a maximum voltage of 90 volts. The cathode isconnected frorn terminal 35 to ground through resistor iii.

The impulses generated in resistor 61 are applied to the Wide bandamplifier 36 by the cou pling condenser 62 which is connected to thecontrol grid of the amplifier 44. The control grid is also connected toground through resistor 53. The cathode of amplifier tube 44 isconnected to ground through a cathode bias circuit utilizing resistor 64and condenser 65. The screen voltage is obtained from the power supplythrough the series resistor 66, and the screen grid is also connected toground through condenser 61. Voltage is applied to the plate of the tube44 through the series resistor 68. Amplifier tube 45 together with itsassociated circuit elements 69, 10, H, l2, i3, 14 and 15 comprise anamplifier stage identical to the'preceding one.

The output of the amplifier stages is coupled through condenser 15 tothe junction of condensers I1 and 18 which condensers are connected tothe grids of thyratrons 46 and 41 respectively. The grids are alsoconnected through resistors 19 and 80 to the negative terminal of a biascell The condensers 88 and 89 which are connected respec-' tively to thegrids of thyratrons '43 and 49. These grids are also connected throughresistors 90 and ill to the negative terminal of bias cell 92 whosepositive terminal is connected to ground. The plate of tube 48 isconnectedto armature 84 through resistor 93 and to the plate of tube 49by condenser 34. The plate of thyratron 48 is connected to B plusthrough the operating coils of relay 95, a single pole double throwrelay whose armature 95 is connected to the shield grid of thyratron 5nand whose contacts are connected to negative tap terminals V1 and V2 onthe power supply 43, and of relay 9], a double pole time delayrelay withone normally open contact and one normally closedcontact; Normallyclosed contact 98 of relay 9'4 is connected to the high voltage tap ofthe power supply 43 while armature 99 is connected to the B plusterminals of each of the stages of the circuit; Armature I operates thenormally open contacts of relay 9? and armature me is connected to thehigh voltage terminal of the power supply 43. Normally open contactpoint I0! is connected to terminal 142 of Fig. 13. Terminal I93 of Fig.13 is con-. nected to ground.

The output of the amplifier 35 is coupled to the grid triode tube 5!,connected as a limiter, by condenser I02. ground by grid leak resistorI45. The cathode of the tube 5| is connected to ground through a cathodebias circuit comprised of resistor I05 and condenser iil'l. The plate isconnected to B plus through the series resistor I08 and to the controlgrids of the starting stage thyratron 50 and of the information stagethyratrons 52, 53 and 54 by condenser N19.

The cathode of starting stage shield grid thyratron 50 is connected toground and its plate is connected to B plus through the operating coilof relay i ll), a six pole normally closed relay whose contacts A1 to A6inclusive are connected to the grids of the timing thyratrons 55 to 64inclusive, respectively. 1

All of the information stages 40, 4! and 42 are identical to one anotherexcept for the specific values of the resistors and condensors in thegrid circuits of the timing thyratrons 55, 56, 51, 58, 59 and 53. Eachinformation stage utilizes shield grid thyratron 52, 53, or 54,'to whosecontrol grids the positive signal pulses are delivered from the limiter33 by the condenser IDS. The shield grid of each tube is connected toground and the cathode of each is connected to the midpoint of a voltagedivider comprised of resistors Ill and H2, H3 and H4, or H5 and H6. Theplates of thyratrons 52, 53 and 54 are connected to B plus through theoperating coils of relays I H, I I8 and l l9 respectively. The alertingthyratrons 55, 56 and 51 have R-C circuits comprised of condensers I23,[2| and I22, respectively, and resistors I23, I24, and I25,respectively, connecting from grids to ground. The cathodes of the tubes55, 56 and 51 areconnected to ground and their plates ar connected to Bplus through ter- The grid is also connected to i minals I26, I21 andl23respectively of relays I29, I30 and I3I respectively throughresistors I32, I33 and I34 respectively. Resistors III, H3 and I I5 ofthe voltage dividing networks are connected respectively to the secondset of contacts of relays I29, I30 and I3I and thence respectively tothe plates of tubes 55, 56 and 5 1. The stopping thyratrons'53, 59 and60 have R-C circuits comprised of condensers I35, I36 and I31respectively and resistors I38, I39 and M respectively connected fromtheir grids to ground; their cathodes are connected to ground and theirplates are connected to B plus through the operating coils of the doublepole, normally closed relays I23, I30 and I3I respectively.

Fig. 16 indicates the voltage wave generated in resistor 6| as thephototube 33 scans the image of the target I2. The scanning isalternately to the right and to the left. Because of the particulardesign of the target, the same pulse train results from scanning ineither. direction. For the purposes of this disclosure, the scanningdirection is arbitrarily assumed to be from left to right. Each sectionof this wave will be traced through the system to disclose the operationof the circuit. The first three pulses I4I, I42 and I43 are generated asthe photocell 33 passes the information lines 1, 8 and 9 of the targetI2 they are at the relatively low voltage amplitude Va because of theirrelatively poor light reflecting quality. If the gain of the amplifier36 is A, then these pulses will appear with an amplitude Ave at theoutput of the amplifier 36 and at the input to the counting circuit 31and the limiter 38. The counting circuit 31 is adjusted so that it willonly respond to pulses whose amplitudes are greater than Ava, so thisseries of pulses will have no effect on the counting circuit. Thelimiter 38 is adjusted by means of its associated circuit in such amanner that the-greatest amplitude of voltage applied to the succeedingstages will be AVa. Thus, the first series of pulses with an amplitudeof Ava will be applied to the control grids of the shield gridthyratrons 50, 52, 53 and 54. Since the shield grids of each of thesethyratrons is highly negative with respect to the cathodes at this time,pulses of amplitude Ava will have no effect on these tubes.

The next pulse I44 is generated by the signal ring 6 of the target I2.Since this pulse is of the same amplitude, Ava, as the previous pulses,it will have no effect on the information stages 40, M and 42, or on thealerter 31.

The series of pulses I45, I46, I41, I48, I43, I50, I I and I52 aregenerated as the photocell 33 passes the signal rings III in the centerof the target I2 and, because of their relatively good reflectingqualities, are at a higher amplitude than Va, namely Vb. These pulsesI45 through I52 are amplified by the amplifier 36, appear at its outputas pulses of amplitude Ave, and are of great enough amplitude to operatethe alerter stage, with the result that the circuit counts the pulses.The first of the series of pulses I45 through I52, fires tube 46. Thesecond extinguishes 46 and fires 41. The third fires 46 again. Thefourth extinguishes 46 and 41 and fires 49. The fifth fires 46. Thesixth extinguishes 46 and fires 41. The seventh fires 46. The eighthextinguishes 46, 41 and 46 and fires 49. An examination of the sequencereveals that during the normal cycle tube 46 is never firing for alonger period than a seconds. This fact is made use of in the followingmanner, to prevent extraneous pulses from completing the alerting cycle:Relay 8. 82, which is in the plate circuitof tube 46, is designed tooperate only if tube 46 is in a conducting state for a period longerthan a" seconds. Thus, if some pulse fires tube 46 and no other pulsesappear in the normal sequence, relay 82 will operate and remove B plusfrom tubes 46, 41 and 48 and clear the counter. As soon as relay 82causes tube 46 to be extinguished, the armature of relay 82 is releasedand the circuit is ready to count again. If the entire sequence of eightsig nal pulses appear, tube 49 will fire and operate relays 95 and 91.Relay 95 causes a less negative voltage to be applied to the shield gridof the thyratron 50 and any succeeding pulse applied to the control gridwill ignite it. Relay 91 is designed to operate B seconds after tube 49has fired and to remove the B plus supply from the entire circuit thusextinguishing all of the thyratrons and preparing the circuit for a newcycle when the contacts are released. Relay 91 also operateathroughterminals I02 and I03, relay I51, of Fig. 13, which controls the packageremoval mechanism. The same series of pulses I45 through I52 is appliedthrough the limiter 38 to the thyratrons 53, 52, 53 and 54, but sincethe tube 50 is not alerted by the alerter 31 until after the last pulsehas appeared, these pulses have no effect on the starting stage 39 orthe information stages 40, M and 42.

Pulse I53 appears during period c as photocell 33 passes starting ring 6of the target I2 again. The pulse of amplitude Va generated by startingring 6 is applied to the amplifier 36 and the pulse appears at itsoutput with an amplitude AV. This pulse has no effect on the alerter 31,but is passed by the limiter 38 and is applied to the starting stage 39and the information stages 40, 4| and 42. The starting tube 59 is now insuch a state due to the operation of relay that this pulse applied toits control grid will ignite the tube 50 and operate relay I I6.Operation of relay IIO removes the negative voltage from each of the R-Ccircuits connected to the grids of thyratrons 55 through 60, inclusive,and allows the electrons stored in condensers I20, l2l, I22, I35, I36and I31 to leak oil through resistors I23, I24, I25, I38, I39 and I40.When the voltage becomes high enough on the grids of tubes 55, 56 and 51they fire and reduce the voltage across the voltage dividers III throughII6, thus reducing the difference in voltage between the shield gridsand cathodes of thyratrons 52, 53 and 54. This alerts each of thesetubes and allows it to fire if a pulse appears upon its control grid.The constants of the R-C circuits connected to the grids of tubes 55, 56and 51 are adjusted so that tube 55 will fire at t1, tube 56 will fireat t: and tube 51 will fire at t3. The associated circuits of tubes 58,59 and 60 are adjusted so that they will fire at in, t3 and 154respectively and the firing of each of these tubes operates relays I29,I30 and I3I, respectively, removes B plus from each of the tubes 55, 56and 51, extinguishing them in turn, and increasing the differences inpotential between the cathodes and shield grids of tubes 52, 53 and 54respectively. The result is that tube 52 can be ignited by a pulse I54on its control grid only during period 11 and tube 53 can be ignited bya pulse I55 on its control grid only during period c, and tube 54 can beignited by a pulse I 56 on its control grid only during period 1. PulsesI4I, I42, I43, I54, I55 and I56 may or may not'be present, dependingupon what information is coded in the pattern being scanned.

, Theclosing of relay II1 indicates that the first .91. The

information line 1, correspondingto 2", is present which has just passedthe electric eye element I5,

in classification 6. The relays H1, H8 and H9 can be caused to operatetabulating, computing and/or sorting machines.

The closing of the normally open relay. I51 of Fig. 13 is accomplishedby the closing of relay closing of relay I51 indicates two things:Firsig'the scanning mechanism of Fig. 12, used in conjunction with theelectronic circult of Fig. 15, has seen and recognizedthe centralportion I of the target I2; and, second,

enough time (1) seconds) has elapsed for the whole target to have beenscanned; Although the receipt of operating energy through terminals I02and I03 of relay I51 is only momentary, the relay I51 when once closedwill be held closed by the holding coil energy supplied from the cellI58 through normally closed limit switch I59 and the set of normallyopen contacts I60.

The closing relay I51 also closes contacts I6I which delivers energyfrom the source of potential I62 through solenoid I63 to terminals I64and I65 of motor I66 (Fig. 11). the chain I61, the motor I66 causes theshaft I68 to revolve, which results in the oscillation of the carriageI69 due to the effects of pin I10, fixed bar HI and thread I12 in thesame manner as the corresponding elements of Fig. 12 cause the carriage21 to oscillate. A pusher I13 is fastened to the carriage I69 by setscrew I14. Pusher I13 travels across the belt in a direction parallel toscanning plane A-A pushing onto the delivery chute I1 any package IIwhich happens'to be in its operating range. The motion of the pusher I13always begins at the extreme left end of its travel and the motion islimited to one cycle per. closing of relay I51. This is lo ecause theholding circuit is broken by the opening of the limit switch I59 byscrew I15 with the result that the motor is stopped. The opening ofrelay I51 deenergizes solenoid I63 and the spring loaded plunger I16 isforced against shaft I68. Inertia causes shaft I68 to continue torevolve until plunger I16 enters hole I11 and shaft I68 abruptly andprecisely stops. Screw I15 is so adjusted that it engages contact buttonI18 on limit switch I59 at the extreme end of travel of carriage I69,and coasts away from button I18 before plunger I16 enters hole I11. Whenrelay I51.closes and causes the motor I66 to be enengized relay I51 alsocauses the solenoid I63 to be energized, thus withdrawing plunger I16from hole I11 and allowing shaft I68 to be revolved.

In the foregoing description it has been assumed that the objects to beclassified, such as represented by the packages II in Fig. 11, have theclassifying information applied thereto and are scanned by thephoto-sensitive apparatus. However the classification may be carried outby means of tokens of the actual objects, in which case the tokens wouldbear the classifying information and would be scanned by the apparatus.Therefore, the word article, as used in the By means of claims, isintendedto mean either the objects bing classified'or their tokens.

It should be noted further that in a broad sense the apparatus'efiectsclassification of information represented by the markings, and theapparatus can be used as a means for classifying information wheneverdesired.

From the foregoing description, it will be seen that the inventionprovides a novel classifying apparatus which may be used for variouspurposes. It will be understood, of course, that the values of thecircuit elements will be determined in any instance by the particularoperating circumstances. Moreover, the invention is capable of variousembodiments and is not limited to the particular embodiment illustratedand described. We claim:

1'. Apparatus for classifying articles having thereon concentriccircular light-reflective outer classification lines and inner auxiliarylines; comprising means for continuously moving the articles in astraight path past a scanning position;

. scanning means at said position for producing electrical pulsescorresponding to said lines; means for oscillating said scanning meanstransversely of said path to effect scanning diametrically of thecircular pattern on each article; a plurality of normally-inoperativeelectronic classifying devices; electronic means responsive to thepulses corresponding to said auxiliary lines for conditioning saiddevices for operation; and means for effecting operation of saiddevices, by the pulses corresponding to said classification lines, in apattern corresponding to the pattern of the classification lines on eacharticle.

2. Apparatus for classifying articles according to difierent identifyingcombinations of a predetermined number of positionally characterizedclassifying markings on the articles, comprising means for producingelectrical pulses in time spaced relation corresponding to thepositional characterization of said markings, a plurality ofnormally-inoperative classifying devices, means for rendering saiddevices successively operative in time sequence corresponding to thetime sequence of said pulses, and means for supplying said pulses to allof said devices, whereby said devices are operated according to thepattern of the classifying markings on an article.

3. Apparatus for classifying articles havin provided thereonpositionally characterized classifying markings and auxiliary markings,comprising means for producing electrical pulses corresponding to saidmarkings, a plurality of normally-inoperative classifying devices, meansoperable by the pulses corresponding to said auxiliary markings forrendering said devices successively operative in time sequence accordingto said classifying markings, and means for supto all of saidthyratrons, whereby said thyra-.

trons are operated according to the pattern of the classifying markingson an article.

5. Apparatus for classifying articles having provided thereonpositionally characterized classifying markings and auxiliary markings,comprising means for producing electrical pulses corresponding to saidmarkings, a plurality of thyratrons, a plurality of relays operablerespectively by said thyratrons, means operable by the pulsescorresponding to said auxiliary markings for rendering said thyratronssuccessively operative in time sequence according to said classifyingmarkings, and means for supplying to all of said thyratrons the pulsescorresponding to said classifying markings.

6. Apparatus for classifying articles having provided thereonclassification markings. and auxiliary markings; comprising a pluralityof normally-inoperative classifying devices; means responsive to saidmarkings for producing electrical pulses; means including an electroniccounter responsive to the pulses corresponding to said auxiliarymarkings for conditioning said devices for operation; and means foreifecting operation of said devices, by the pulses .correspending tosaid classification markings, in a pattern corresponding to the patternof said classification markings on each article.

'7. Apparatus for classifying articles having provided thereonclassification markings and auxiliary markings, comprising a pluralityof normally inoperative classifying devices, means responsive to saidmarkings for producing elec trical pulses, means responsive to pulsesproduced from certainof said auxiliary markings for rendering saiddevices operative, means responsive to a starting pulse produced fromone of said auxiliary markings for starting operation of said devices,and means for supplying to said devices the pulses produced from saidclassification markings,

8. Apparatus for classifying information in re sponse to a patternincluding a series of markings of predetermined number and othermarkings representing information, said apparatus comprising means forproducing time-spaced pulses corresponding to said markings, anelectronic counter coupled to said means to receive pulses correspondingto said series of markings, a plurality of normally inoperativeclassification devices, means for rendering said devices operative uponcompletion of a counting operation by said counter, and means forsupplying to said devices the pulses corresponding to said othermarkings.

12 9. Apparatus for classifying information in response to a patternincluding a series of markings of predetermined number, astartingmarking and other markings representing information, saidapparatus comprising means for producing time-spaced pulsescorresponding to said markings, an alerter stage coupled to means andoperable by the pulses corresponding tofisaid series of markings, astarting stage coupled to said alerter stage and conditioned thereby foroperation, means for effecting operation of said starting stage inresponse to the pulse corresponding to said starting'marking, andinforms-- tion-classifying stages rendered operable by said startingstage and connected to receive the pulses corresponding to said othermarkings.

10. Apparatus according to claim 9, wherein said alerter stage comprisesan electronic counter, and the starting and classifying stages includeshield grid thyratrons.

11. Apparatus for classifying information in response to a patternincluding concentric circular outer classification lines and innerauxiliary lines; comprising means for scanning diametrically of saidpattern and for producing electrical pulses corresponding to said lines;a plurality of normally-inoperative electronic classifying devices;electronic means responsive to the pulsescorresponding to said auxiliarylines for conditioning said devices for operation; and means foreffecting operation of said devices, by the pulses corresponding to saidclassification lines, in a pattern corresponding to the pattern of theclassification lines.

NORMAN J. WOODLAND. BERNARD SILVER,

REFERENCE S CIT ED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,985,035 Kermode Dec. 18, 19342,020,925 Young Nov. 12,1935 2,224,646 Friedman Dec. 10, 1940 2,280,948Guliksen Apr. 28, 1942 2,358,051 Broido Sept. 12, 1944 2,400,574 Rea May21, 1946 2,441,596 Reitter May 18, 1948 FOREIGN PATENTS Number CountryDate 256,223 Great Britain Sept. 1, 1927

